The invention resides in an anchor for mounting to lightweight construction panels including a central support core covered at opposite sides by first and second cover plates, wherein the anchor comprises at least one expansion body with mounting means and at least one wedge body movably disposed in the expansion body.
Flat lightweight construction panels with support cores are often also called sandwich panels, honeycomb panels or lightweight panels. All types of panels used in furniture construction generally have cover plates of thin wood chip plates, medium or high density fiber plates, plywood or hard fiber plates. As central cores or support cores of the sandwich plates, sheets of foamed polyurethane or polystyrol are often used. In honeycomb panels support cores of corrugated web inserts or so-called expanded honeycombs are used as intermediate layers. Most lightweight panels have a density of less than 500 kg/m3. If for the intermediate layers no fire-retardant aluminum foams or foamed glass is used, the raw density is generally less than 350 kg/m3.
If armatures have to be attached to the lightweight panels for example by means of screws, it is a problem that the attachment means can be connected generally only to the relatively thin cover plates or cover layers. To resolve this problem, generally expansion anchors are used as they are disclosed for example in DE 20 2004 000 474 U1. This type of expansion anchors however have the disadvantage that they engage the top cover plate at opposite sides thereof over a large area. The rear engagement fingers displace the support core material in the area around the bore into which the anchor is inserted whereby the cover plate is released easily from the core support material and lifted off when the anchor is subjected to pulling forces.
Another anchor which avoids the disadvantage referred to above is known from the internet brochure (September 2006) of the company Fischer Befestigungssysteme GmbH. It is offered herein under the designation SLM-N. The anchor has a tubular expansion body with a bore in part of which a wedge body is accommodated which is frustro-conical in shape and has a slotted rear expansion body end. The wedge body has a central bore with an internal thread. When for example the wedge body is pulled by tightening a mounting screw disposed in the thread of the wedge body into the expansion body, the expansion body is expanded into tight engagement with the lower part of the bore. However, this anchor could be tightly held only if the core support material would be very rigid.
It is further known from DE 10 2006 049 952 to provide in the central opening of an anchor a bladder filled with a cement. The bladder is ruptured upon insertion of a wedge body whereby the cement is released and the anchor is cemented to the lower cover plate.
It is the object of the present invention to provide an anchor for lightweight construction panels which is easy to install and can be safely and durably retained in the light-weight construction panel. It is not intended for mounting to solid panel inserts or the respective panel transverse members.